William arthur



Patented Oct. 4, I898.

No. sn,74a. w. ARTHUR.

WATGHCASE SPRING.

(Application filed Apr. 27, 1897.)

(No Model.)

lIl1||IIlllIlllllllllllllllllilllllllll INVENTOR M at A TTORIVEY WITNESSES:

UNITED STATES PATENT OFFICE.

WILLIAM ARTHUR, OF NEWARK, NEl/V JERSEY, ASSIGNOR TO THE NElVARK WATCH CASE MATERIAL COMPANY, OF SAME PLACE.

WATCHCASE-SPRING.

SPECIFICATION forming part of Letters Patent No. 611,748, dated October 4, 1898.

Application filed April 27, 1897.

T0 ail whom it may concern:

Be it known that 1, WILLIAM ARTHUR, a citizen of the United States, and a resident of Newark, in the county of Essex and State of New Jersey, have invented certain new and useful Improvements in WVatchcase-Springs, of which the following is a specification.

My invention relates to an improvement in watchcase-springs, the object of the same being to provide an article of this kind or character which shall be simple in construction, cheap to manufacture, durable and efficient in use, and which may be readily and easily adjusted in place and to a great extent obviate the difficulty which has heretofore existed in properly tapping the body of the spring to ble hardening or tempering the body thereof, for when such occurs it is difficult to tap the same to receive the retaining-screw. In some instances a number of holes have been formed in the body of the spring before tempering in order to make certain that one of such will register with a hole made in the watchcase-center and through which latter the said retaining-screw is passed. To avoid the necessity of drilling a number of holes and in order to avoid the care required to temper the restricted neck only of the spring is another object of my invention, which consists in stamping the spring out of sheet-steel of the proper thickness and with a suitable elongated opening and notch therein, then partially bending and shaping the spring to its desired form, then inserting a core of soft metal, and finally bending and shaping the spring into its finished form, after which the article is hardened or tempered in anydesired manner. The core, which is inserted within the body of the spring or, in other words, around which the sheet-metal body of the spring is bent, is formed of such metal as will not harden or temper during the temper- Serial No. 634,122. (No model.)

ing of the sheet-metal body, the effect being that by reason of the elongated openings left in the sheet-metal body of the spring where the hole or holes are usually drilled for the reception of the retaining screw the softmetal core only need be drilled instead of the entire thickness of the body.

iVhile it is evident that my invention is applicable to both the lock and lift springs, I have illustrated in the drawings the lift-spring only.

Figure 1 is a view of the blank, preferably stamped from sheet-steel of the desired thickness. Fig. 2 is a side View of the soft-metal core. Fig. 3 is a sectional view of the spring, showing the body partially shaped and the soft-metal core inserted therein. Fig. i is a similar view of the finished spring. Fig. 5 is a perspective view of the finished spring. Fig. 6 is a sectional view taken on the line 5 5 of Fig. 5.

By reference to Fig. l of the drawings it will be seen that the springrblank consists of the body A and restricted neck B, the latter being provided on its extreme end with the projection Cb, adapted to bear against the back or lid of a watchcase and raise the same when released by the lock-spring. This blank is preferably stamped out of sheet-steel of the desired thickness and has one of its edges near the end of the body out out or recessed, as shown at h, and is also provided with the elongated opening 0, which in the finished spring is in line with the recess 1) and through which opening 0 passes the retaining-screw (not shown) for holding the spring in position in the watchcase.

The blank after being formed as above de- Q scribed has the body A bent or turned over, as shown in Fig. 2, after which operation the metal core 0 is inserted therein, said core being formed of a metal that will not harden or receive a temper during the hardening of the body Asuch, for instance, as softsteel or brass and may be in the form of half-round wire, square, or other shape, but preferably conforming in shape to the body of the finished spring.

By means of suitable dies the body A of the spring is then closed, as shown in Fig. 4, and the article curved in the direction of its too length to conform to the curve of the watchcase-center, after which it is subjected to heat or to any desired process for hardening and tempering the same.

From the above it will be understood that my improved spring retains all of the essential features of the old form of solid spring, and while retaining the desired features and qualities thereof for instance, such as weight, stiffness, and a means for supporting the case-centerit overcomes many objections heretofore urged against it and necesst tates the drilling of soft metal only.

If desired, the notch or recess 1) may be omitted. It often happens, however, that the only way in which to remove the retainingpin is by forcing it down through the spring and out of the lower side, and hence in such instance the opening in the lower portion of the sheet-metal body formed by the recess Z) would be necessary. Again, in drilling the hole 0 in the soft-metal core, as shown in Fig. 6, for the reception of the retaining-pin it is possible that the drilling-tool might strike the tempered sheet-metal body unless said opening or recess were made and thereby damage the drill or tool.

I am aware that springs have heretofore been constructed of sheet metal to which has been secured a soft-metal back for receiving the retaining screw; but in my improved spring the objectionable features of said former backed spring-to wit, the use of solder or rivets for affixing the back of the spring properare avoided.

Having fully described my invention, what I claim as new, and desire to secure by Letters Patent, is-- 1. A watchcase-spring the body of which is formed of sheet metal bent as described and provided with an opening, and a softmetal core contained within said body, substantially as described.

2. A Watchcase-spring the body of which consists of tempered sheet metal bent as described and provided with an elongated opening, and a soft-metal core contained within said body, substantially as described.

Signed at New York, in the county of New York and State of New York, this 15th day of April, A. l). 1897.

\VILLIAM AR'lIlUR.

\Vitnesses:

F. S. KENNEDY, GEORGE COOK. 

